Hand-brake mechanism



March 10, 1931. w. H. JOHNSTON HAND BRAKE MECHANISM Filed Aug. 26, 19272 Sheets-Sheet 1 March l0, 1931.

w. H. .JOHNSTON HAND BRAKE MECHANISM Filed Aug. 26, 1927 2 sheets-sheetl2 Patented ar.. 10, 1931 WILLIAM H. JOHNSTON, or rnoczron., MINNESOTAHAND-BRAKE 'MEGHANISM Appucatidnmea August ze, 1927. serial No. 215,612,

The invention pertains to a hand brake,y

' and more particularlyv to a hand brake booster of such constructionand disposition of parts that there will be a quick initial take-up ofthe .5 brake chain without necessairly enlarging or multiplying a-nyparts of the brake staff connections.

' It is a requirement of the AJR. A. that the hand brake power must beequal tothe power developed by the air brake cylinder with fifty poundsair pressure per square inch. This recommendation is commonly made byincreasing the length of the' cylinder lever, or an vauxiliary lever,sheave wheel, etc., which method is obj ectionablel in that an excesslength of chain is required to be wrapped aroundA the brake stad drum,which requires a greater length of time to set the hand brakes with thepossibility that the excess chain will lap or foul itself when woundaround the brake staff drum. Diiiiculty has always been encountered inobtaining4 the speed necessary for a. quick take-up ofthe chain,together with the proper power for the brake application, due to thefact that devices designed to produce both of these effects arecomplicated and are expensive.

It is therefore an object of the invention to rovide a simple, eifectiveand positive device or insuring obtaining hand brake power equal to thatpower developed 'by the `air brakecylinder at fifty pounds airpressureper square inch without increasing either the size or unduly increasingthe number of the brake controlling parts. s

Another Objectis to provide a'mechanical movement of such nature anddisposition of parts as to provide an advantage in the initial movementof the hand brake mechanism.

Still another object is to provide a mechanism of such character as willafford a quick initial take-up of the brake mechanism, yet which mayreadily be placed on a car so as not to occupy otherwise useful space.

A further Aobject is to provide a hand brake booster which reduces thetime element to bring the brake shoes in contact with the carc wheelsand produces a multiplying power t'o meet the requirements of the-A. R.A.

A still further obiect is to provide a mulnism is connected tooperatingmechanism --by pull and/or push rods. Other, various and more specificobjects will readily occur from the detailed descrip- I.

tion and drawings appended hereto'.

In the drawings, wherein like reference characters are used to designatelike parts- Figure 1 is a plan view of a car underframe, showing therelation of the brake cylinder with the brake lever and hand brakebooster in released position;

Figure 2 is a side elevation of one end of a car, showing the connectionbetween the brake staif rod and\sta1 drum;

Figure 3 is a plan view showing the disposition of the parts of thebrake staff booster in brake release position, similar to Figure vl, andindicating intermediate positions for illustrating thev relation of thetravel of the hand brake connection to that of the brake cylinderconnection.

Figure 4` 's a partial elevation of one end of a hopper car showing theapplication o'f a modication of the brake system thereto;

Figure 5 is a partial'plan of the brake setting mechanism shown inFigure 4; and

Figure 6 is an enlarged sectional elevation of the multiplyingmechanism, taken substantially on the plane as indicated by the line 6-6of Figure 4. A

Referring more particularly to the embodiment shown'in Figures 1 to 3inclusive, the usual car underframe X, comprising members 30, 31, etc.,is adapted to carry vthe hand brake booster Y disposed on a bracketbetween longitudinal and transverse members,

The longitudinal member or sill 30 supports the brake cylinder 33 by anymeans, such 'as a bracket 34. The cylinder is provided ing brake lever36 having the brake shoe rods 37 and 38 pivoted thereto. The piston 35is also pivoted to some means, such as the rod 39, having the spring 40surrounding and cowith the usual piston 35 pivoted to the floata bracketor rod bearing 41 providing a per sheet.

Ishoulder for the spring 40, and is attached to a link 42 pivoted tothefulcrum A of the series of links lcomprising the hand brake booster.

Also ulcrumed at A and pivoted y'to the bracket 32 at C is a link 43."Link 44, also pivoted at A, has its opposite end pivoted at a point Eintermediate the points D and B of the link 45, said points beingpivoted respectively to the bracket 32 and to the hand brake rod 46.This rod at its opposite end is provided with a suitable length of chain47 attached to the drum ofthe brake stall:`

48 supported on the bracket 49, said. chain being adapted to be Woundaround said dru to cause the setting of the brakes. Referringparticularly to Figure 3, it will vv"be seen that when the appliedtravel of the point B, operated by the hand brake, is one inch, thetravel of the brake cylinder rod, that is, point A, which it will beunderstood sets the brakes through the brake lever 36,

is slightly over two inches, as indicated atV land 53 respectively,supported on `a portion bf the underframe under the sloping end hop-These cylinders may be vof the usual fluid' type, having pistonsconnected at 54 and 55 respectively to a oating brake operating lever 56pivoted at one end at 57 to a portion of the car underframe. Thispivoted lever is pivoted at 58 to a link 59 which in turn is pivoted at60 to the floating brake lever 61 vhaving the lusual brake shoeoperating rods 62 and 63 pivoted at thek ends thereof. An end hopperstrut 64. may be conveniently used for supporting a bracket 65 carryingthe .multiplying lever mechanism. This mechanism consists of a lever 66pivoted to the bracket 65 at 67 said lever 66 being provided with afloating ivot 68 for attachment of the link 69 whic is pivoted byanother ioating pivot 70 to a'link 71 pivoted iently supported bytheunderframe 51. Any suitable connecting means, such as a chain 74, may beconnected at the floating vpivot 70 to the multiplying mechanism, theother end of said chain being connected to a hand brakestal which may beconveniently carried by a suitable mounting 76, said staff beingprovided at or near its upper end with any convenient actuating lever77. Pivoted to the Hoating pivot 68 is a push rod 78 pivoted at itsother end at 79 to the floating brake lever operating lever 56, saidpivot point 79 being remote from the pivot point 57 of said lever.Attached to the underframe, there may be provided a guide or track at 72to a bracket 73 which may be convenand E will move on their respectivearcs.4

The point B moving on arc B, B will cause the point E to move on an arcE, E", causing the point A of the links 43 and 44 to travel in the arcA, A', pivoting around C to corresponding positions determined by theosition of the point E and the' length o 'the link 43. Like numbers onthe various arcs represent like positions at any time. As the point Atravels, it will be understood that the* link 42, rod 39 and piston 35will move in the direction of the point A, compressing the spring andthereby causing movement of the floating member 36 which will cause asetting of the brakes. It is desirable that only about seven inches, orat the most nine inches, of chain be wound around the brake drum toprevent lapping of the chain,` andit will be seen by a referenceto thesuccessive points 1, 2, 3 to 7 on the arc B, B', and the correspondingpoints 1, 2, 3 to 7, that for this travel there is a quicker initialmovement vof the point A, and therefore of the vbrake lever, than thereis o' the point B corresponding to the travel of the rod 46 for theamount of chain wrapped around the brake. This relation of the movementbetween the pointsB i and A produces an amplifying power on the brakeand also insures a quick initial take-up of the chain and a limitedamount of brake chain wound around the brake drum.

In the modification of the device shownv in Figures 4 and 5, it will bereadily u nder.

tio'n of the mechanism, the point 68 will move I a greater distance thanthe point 70. This then will cause the push rod 78 to move toward theright, rotating the leverv 56 around the point 57, thereby causing theoating brake lever 61 to set the brakes. It will of course be'understood that whenthe brakes are set by fluid actuation, the pistonsof the operating cylinders will be moved toward the right, causing thelever 56 to rotate around the point 57, setting the brakes through thefloatingV lever 61. Qn release of I the hand brake or operatingcylinders, the

brakes may be released either by introducing f air into the operatingcylinders or by suitable springs provided in said cylinders for thatpurpose. p It is to be understood tha-t the embodiment shown is merelyby Way of illustration and not limitation, as other and various forms ofthe device will vreadily occur to'those skilled in the art.

I claim:

1. In a device of the character-described, the combination of a brakecylinder, a brake staH", and abrake connection between said brakeV staffand brake cylinder comprising a system of levers for operating'thebrake, said levers includinga lever connected to the .brake cylinder andpivoted to the car, a lever the combination of a brake cylinder, a brakestai, and a Abrake connection between said brake staff and brakecylinder comprising a system of levers for operating the brake, saidlevers comprising a lever connected to thel brake cylinder and pivotedto the car,fa lever connected to the brake staff and pivoted tov thecar, and a Hoating means pivoted to said levers between' the brakecylinder and the staii' connection. y

4.. In a device of the character described, the combination of a brakecylinder, a brake staff, and a brake connection between said brake staffand brake cylinder comprising a system of levers for operating thebrake, said levers comprisingl a lever connected to the brake cylinderand pivoted to the car, a lever connected to the brake stal` and pivotedto the car, and a lever pivoted tosaid levers between the brake cylinderconnection and the stai connection.

v7. A hand brake booster com rising a bracket, a member pivoted to, saibracket and connected to the hand brake, a brake beam operating meanspivoted to the bracket,

and a Hoating member pivotally connecting said pivotedA member and saidmeans, said Hoating member -being of such length and so positioned thatmultiplying power and quick initial take-up is effected by operation ofthe hand brake.

8. In a device of the character described,

the combination ofv a plurality-of operating mechanisms,fa ymultiplyingmeans -cooperating with said mechanisms to impart quick initial take-upwhen vsettin brakes, said means including a plurality o pivoted leversconnected by a Heating pivoted lever, a connection from one of theHeating pivots to one of said mechanisms, and connections from the otherof the Heating pivots to the' brakes.

9. In a device 'of the character described, the combination of aplurality of operating mechanisms, a multiplying means cooperating withsaid mechanisms to impart quick initial take-up when setting brakes,said means including a plurality of pivoted levers connected by aHoating pivoted lever, connections from one of the Hoating pivots` tooneof said mechanisms and said brakes, and a connection from one of saidpivoted members to the other of said mechanisms.

Signed at Proctor, Minnesota, this 16th day of August, 1927.

p WILLIAM H. JOHNSTON.

lll)

5. In a device of theV character described, i.

the combination of a bracket fixed to a c ar, a brake staH', meansconnecting said brake staH to a brake operating means comprising aplurality'of means pivoted to the bracket and connected by a H oatingmeans, and a connection between said brake operating means and thebrakes. v

6. A hand brake booster comprising a bracket, a member pivoted' to saidbracket and connected to the hand brake,a brake beam operating meanspivoted to the bracket, and a Heating member pivotally connecting saidpivoted member and said means.

